The murine gene PL10 was isolated in a search for genes that may play a role in the regulation of spermatogenesis. It is a member of the newly defined helicase gene family. One function proposed for members of the helicase gene family is the regulation of gene expression through translational control. Phase I of this proposal will include research to further characterize the PL10 gene, its expression and protein products, as well as specific courses. Phase II will be dedicated to identifying the function of PL10. Initially, a testis cDNA library will be screened for full length cDNAs corresponding to the 3.2 and 3.7 kb testis-specific PL10 transcripts. The differences between these two transcripts will be explored through restriction mapping and sequencing. The full length cDNAs will then be used to synthesize the PL10 protein(s) in vitro and generate antibodies against PL10. The antibodies will be used to determine temporal, tissue, cellular specificity and intracellular location of the PL10 protein product. If the 3.2 and 3.7 kb transcripts code for different proteins, specific antibodies will be generated to these proteins to further explore the differences in the two gene products. A mouse genomic library will be screened for the PL10 gene. PL10's gene organization will be characterized via restriction mapping, S1 analysis and sequencing intron-exon boundaries. In Phase II, two different strategies will be employed to identify the function of the PL10 gene. One method will be to experimentally manipulate the expression of the PL10 gene in transgenic animals. The second method will involve complementation analysis of the yeast homolog of PL10. This research experience will provide the necessary knowledge and skills to become an independent researcher and apply this experience to the fields of developmental genetics and reproductive endocrinology.